SDL_Renderer Vulkan Crash on Minimize

[CasualPokePlayer]

Within SDL_UnlockTexture, VULKAN_EnsureCommandBuffer gets called. Within that function rendererData->commandBuffers may be dereferenced, and it might do so while it is currently NULL, causing a crash.

This seems to happen whenever minimize occurs, with SDL_RenderPresent -> (SDL_LockTexture ->) SDL_UnlockTexture being done (rendererData->commandBuffers is set to NULL in SDL_RenderPresent due to VK_ERROR_OUT_OF_DATE_KHR error path, SDL_UnlockTexture proceeding to call VULKAN_EnsureCommandBuffer and dereference rendererData->commandBuffers. This code pattern is currently done within my own app.

[slouken]

I see the potential crash, but I'm not able to reproduce it. Do you have a minimal test example and repro steps?

[CasualPokePlayer]

#include <SDL3/SDL.h>

int main(void)
{
	SDL_Window* window = SDL_CreateWindow("Vulkan Crash Repro", 640, 480, 0);
	SDL_Renderer* renderer = SDL_CreateRenderer(window, "vulkan");
	SDL_Texture* tex = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STREAMING, 64, 64);
	while (true)
	{
		SDL_Event event;
		while (SDL_PollEvent(&event))
		{
			if (event.type == SDL_EVENT_QUIT)
			{
				return 0;
			}
		}

		SDL_RenderPresent(renderer);
		void* pixels;
		int pitch;
		SDL_LockTexture(tex, NULL, &pixels, &pitch);
		SDL_UnlockTexture(tex);
	}
}

Click the Minimize button, crash.

[slouken]

Perfect, thanks!

[slouken]

So as I suspected, unlocking the texture kicks off a buffer upload which uses the current command buffer, so it looks like this just fails when the game is minimized.

That's not ideal, but I'm not sure how games normally handle this. @thatcosmonaut, @TheSpydog, do you have insight here?

[slouken]

The Vulkan GPU renderer doesn't suffer from this problem, so there's probably just some reorganization that needs to happen in the Vulkan renderer.